The Additional Resources for Pathfinder Roleplaying Game Adventurer's Guide notes that any material that changed when it appeared in this book (and underwent several additional rounds of development) would be the default version once the book's contents appear on the Pathfinder Reference Document. Until then, we've let both versions remain legal, for we're not going to institute a change that requires someone to buy another book to use a previously legal character. When we made that Additional Resources update, we expected the PRD would appear soon afterward. It's looking like it will be a while yet before it shows up, and consternation about one of the archetypes in particular—the lore warden—has been building enough that we're resolving it today.
Officially Updated: The Adventurer's Guide version of the lore warden becomes the sole version used in Pathfinder Society Roleplaying Guild on October 18, 2017. Aim to update your characters using the allowances below before the next time you play a character with fighter (lore warden) levels. This change doesn't become binding for two weeks, which allows you some time to make adjustments and doesn't require you to perform any modifications before your imminent game or convention.
Full Rebuild: If your character had one or more levels of lore warden on or before August 11th, 2017, you can freely rebuild your character as you like. That includes changing up basically anything about the character except the Chronicle sheets you've assigned to them.
Partial Rebuild: If your character took their first level of fighter (lore warden) or otherwise retrained into the lore warden archetype after August 11, 2017 but before October 4, 2017, you can freely rebuild these recently-acquired fighter (lore warden) levels and any other levels taken since; this includes any other character choices you've made since then, such as feats, spells known, recent purchases, and the like. If you adopted the archetype after this date through retraining, you may freely retrain the archetype—removing it entirely or replacing it with one or more other fighter archetypes.
Resources: Both the Pathfinder Campaign Setting: Pathfinder Society Field Guild and Adventurer's Guide are legal sources for the lore warden. If you own the former, simply use the updated text from the Adventurer's Guide, reprinted below.
Lore Warden (Fighter Archetype)
Quick wits and deceptive techniques can often succeed where brute force might not. A lore warden is the consummate warrior-scholar of the Pathfinder Society, outsmarting her competition even when locking blades with powerful foes. Outside of combat, a lore warden's extensive education also helps her document the past and survive great danger.
Scholastic (Ex): A lore warden gains 2 additional skill ranks each level. These ranks must be spent on Intelligence- based skills. All Craft and Knowledge skills are class skills for lore wardens, as are Linguistics and Spellcraft.
This ability replaces the fighter's proficiency with medium armor, heavy armor, and shields.
Skill Over Strength (Ex): At 2nd level, a lore warden qualifies for feats and other abilities as though she had the Combat Expertise feat. At 6th level, she gains Combat Expertise as a bonus feat, even if she would not normally qualify for the feat. If she already has Combat Expertise, she instead gains any one combat feat that includes Combat Expertise as a prerequisite (and for which she otherwise qualifies). At 10th level, she can treat her base attack bonus as though it were 2 higher for the purpose of calculating the effects of Combat Expertise.
This ability replaces bravery and the fighter bonus feat gained at 2nd level.
Swords Secret (Ex): A lore warden learns specialized techniques that help her to quickly analyze and defeat her foes. At 3rd level, a lore warden gains one swords secret, and she gains an additional swords secret for every 4 fighter levels gained after 3rd. Except where noted, a lore warden cannot select the same swords secret more than once.
Exploit Weakness (Ex): The lore warden adds one-third her class level on attack rolls to confirm critical hits. At 11th level, whenever she confirms a critical hit, her weapon attacks ignore the first 5 points of damage reduction or hardness the target has until the end of her next turn. At 19th level, the lore warden can automatically confirm a critical hit once per round when she threatens a critical hit.
Hair's Breadth (Ex): Once per day when subject to a critical hit, the lore warden can attempt an Acrobatics check to reduce the damage as an immediate action. If the result of this Acrobatics check is greater than the opponent's confirmation roll, she negates the critical hit; the attack still hits and deals normal damage. The lore warden must be at least 11th level to select this swords secret. At 15th level she can use this secret one additional time per day.
Know Thy Enemy (Ex): When the lore warden succeeds at a Knowledge check to identify a creature's abilities and weaknesses, she can also use a standard action to grant herself a +2 insight bonus on all attack and weapon damage rolls made against that enemy. This bonus lasts for a number of rounds equal to half her class level (minimum 2 rounds), or until the lore warden uses this ability against a different creature. At 11th level, she also gains a +2 bonus to her AC against the creature when using this ability. At 19th level, the insight bonus increases to +3.
Maneuver Training (Ex): The lore warden gains a brawler's maneuver training class feature, treating her fighter level as her brawler level.
Swift Assessment (Ex): The lore warden can now use her know thy enemy swords secret as a move action. At 15th level, she can use this ability as a swift action. She must have the know thy enemy swords secret before choosing this swords secret.
This replaces armor training and armor mastery.
The enlightened bloodrager and Qadiran horselord archetypes are receiving the same treatment with two exceptions: we're not reprinting the updated archetype text here (it will still await the PRD update), and the date by which any updates need to happen will be based on when the PRD's updated. The cut-off dates for partial and full rebuilds will be the same, however, as will the legality of the respective previous sources for these archetypes. If you would like to perform those rebuilds for characters with those archetypes now, you're welcome to do so.
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